When was Hussein, the grandson of the Prophet Muhammad (PBUH), born?

In the fourth year of the Hijra (Muslims emigration from Mecca to Medina), in the month of Shaban, the grandson of the Prophet Muhammad (PBUH), the second son of Ali and Fatima was born. On the seventh day of his birth, the Prophet Muhammad had two rams sacrificed, recited the Adhan (Muslim call to prayer) into his ears, gave him a name and had his hair cut (all of which are Muslim rituals when a baby is born). Like his other grandson Hasan, Hussein resembled his grandfather as well. For his two grandsons, he always prayed: O lord! I love them. And you love them too. (1)

One day, when Abu Ayyubil Ansari went to the Prophet Muhammad (PBUH), he saw that the Prophet Muhammad (PBUH) was playing with them. When he asked, Do you love them? he told him, Is it ever possible not to love them? They are my sweet basils in the world that I can smell. (2)